These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Anticlimax Boss: The final shootout against Duvall. He's a totally normal enemy with a pistol that happens to kill you in two hits and a ridiculous number of hitpoints.
An interview shows that Ubisoft significantly toned down the anviliciousness. It was originally set in present-day Iraq.
Alternative Character Interpretation: Instead of being offended by the the game supposedly being a commentary on the War on Terror, think of it as a game where you get to play from the perspective of a Mook in a military organization that's a goofy parody of the Combine or the Helghast. The characters suddenly make much more sense.
Big Lipped Alligator Moment: Shane discovers a container ship filled with the bodies of dead Mantel soldiers, all killed due to using Nectar. It's never so much as mentioned thereafter.
In the first mission, you find the pilot of a downed cargo plane, who asks if you can see him, then weakly tells you that he used to be a boxer before joining Mantel. Then he dies. While briefly talked about afterwards, this has no relevance to anything.
Demonic Spiders: The Mantel gun turrets. Hard-to-hit targets with a lot of hitpoints and perfect aim.
After you expose the core of the nectar administrator, everyone starts shrieking/screaming at the top of their lungs. It's hilarious.
Soldier: BUST THIS DOOR DOWN!
Soldier 2: SIR YES SIR! YES SIRRRRRRRRR!
Soldier 3: LOCK AND LOAD MOTHERFUCKERS!
Right afterwards, Shane does a gentle tap to several keyboards, all of which explode for some reason.
Special Effect Failure: A major plot point is that Nectar hides the true horrors of war and makes bodies disappear. Unfortunately, the gore system for the "true horrors" is anaemic (not even putting impact marks on bodies, something GoldenEye managed) and the weak engine means bodies still vanish even when you're a Rebel, it just takes somewhat longer for them to do so.
A more specific failure occurs when a Mantel soldier commits suicide in front of Shane; he draws his pistol and blows his brains blood out, this happening before the pistol actually fires.
In the elevator, Duvall cuts off Merino's right index finger. Throughout the game, Merino is missing his left index finger.
There's another during the "Empty Hands" sequence; here, the player is supposed to see that Duvall has been slaughtering civilians on the basis that their "empty hands" are "just a grip away from holding a gun." Unfortunately, several of them are standard Rebel models, complete with bandoliers full of grenades.
When firing mounted machine guns, neither their actions cycle nor do their ammo belts move.
What Could Have Been: Free Radical planned a sophisticated tactics/partner AI, which would have led to you commanding Mantel/Rebels in some team based combat and helped the game really stand out among FP Ss. Unfortunately, Free Radical couldn't actually get it to work, so they dropped it and this game game became Yet Another FPS.